Williams, seeded No.4 and playing her first match since losing to Stosur in the US Open final last September, lost her serve in the opening game but was never broken again and cruised to a 62 63 victory over Chanelle Scheepers.

"I was a little rusty, not playing since the US Open, but I think I did well," Williams said. "I played a really good player today. It wasn't an easy first round at all. She's had some great wins and I can definitely see why. I've taken some of the rust off - I definitely have tons of room for improvement though."

Awaiting Williams in the second round is Bojana Jovanovski. The two have met once before, with Williams handing the young Serb a 56-minute, 61 61 defeat in the first round of the US Open last year - a victory that improved Williams' record in Grand Slam first round matches to an immaculate 45-0.

"She's a good player. I played her at the US Open, so she knows my game now," Williams said. "I saw her practicing yesterday and she's slamming the ball and moving really well. She's getting ready to play some good matches."

Shortly afterwards, No.2 seed Petkovic completed a see-saw 76(2) 16 63 victory over Shahar Peer. Peer had her chances - she served for the first set twice, then also had an early break in the third - but Petkovic always held on.

"It was really tough, but I expected a tough match," Petkovic said. "I know Shahar very well. She's tough from both sides and her backhand is really a weapon. I'm lucky I was able to get through this match today."

At night, No.1 seed Stosur overpowered Anastasiya Yakimova, 62 63, racing through the first set in 30 minutes but needing 51 minutes to take the second set - including winning a marathon six-deuce game to move to 5-2.